GSTP1 has been considered to be a marker for malignancy in many tissues. However, the existing GST fluorescent probes are unfavorable for in vivo imaging because of the limited emission wavelength or insufficient fluorescence enhancement (six-fold). The limited fluorescence enhancement of GST fluorescent probes is mainly ascribed to the high background signals resulting from the spontaneous reaction between GSH and the probes. In this work, a highly specific GST probe with NIR emission has been successfully developed through optimization of the essential unit of the probe to repress the spontaneous reaction. The novel GST probe exhibits over 100-fold fluorescence enhancement upon incubation with GSTP1/GSH and high selectivity over other potential interference. In addition, the probe has been proved to be capable of tracking endogenous GST in A549 cells. Finally, the in vivo imaging results demonstrate that the probe can be used for effective imaging of endogenous GST activity in subcutaneous tumor mouse with high contrast.

中文翻译：

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优化的荧光探针，用于活细胞和小鼠中谷胱甘肽S-转移酶的特异性成像。

GSTP1被认为是许多组织恶性肿瘤的标志物。然而，由于有限的发射波长或不足的荧光增强（六倍），现有的GST荧光探针不利于体内成像。GST荧光探针有限的荧光增强主要归因于GSH和探针之间自发反应产生的高背景信号。在这项工作中，通过优化探针的基本单位以抑制自发反应，已经成功开发了具有近红外发射的高特异性GST探针。与GSTP1 / GSH孵育后，新型GST探针显示出超过100倍的荧光增强，并且相对于其他潜在干扰具有高选择性。此外，该探针已被证明能够追踪A549细胞中的内源性GST。最后，体内成像结果表明该探针可用于高对比度皮下肿瘤小鼠内源性GST活性的有效成像。